Building Amazon cloud apps that span the world is now much easier

Prepare for outages by copying snapshots from one data center to another.

Amazon's cloud division has rolled out a new feature that makes it easier to build applications that span the globe. Specifically, Elastic Block Store snapshots can now more easily be copied from one Amazon data center to another. In the future, Amazon will provide a similar feature for virtual machines. Ultimately, this will simplify the process developers use to expand the presence of their applications around the world, making it easier to recover from outages that hit specific Amazon data centers.

Amazon Web Services provides on-demand compute and storage capacity to developers who want to build applications without hosting the infrastructure themselves. Amazon's data centers are spread across various regions of the world, including the east and west coasts of the US, Ireland, Singapore, Tokyo, Sydney, and São Paulo. Each region consists of multiple "Availability Zones," allowing separation between the servers and storage hosting your applications. Yet Amazon cloud outages have occasionally taken down multiple availability zones, meaning that customers who demand greater than 99.95 percent uptime must find ways to spread their applications across Amazon regions.

This isn't impossible, but it is difficult, so Amazon's latest move is to make it easier. Yesterday's announcements concern Amazon's Elastic Block Store (EBS) service, which provides block-level storage volumes to be used in conjunction with the virtual machines that host applications. As explained in the Amazon Web Services Blog, EBS Snapshot Copy lets developers copy snapshots from one region to another through the management console or command line. The process isn't completely automated, but in the graphical user interface it can be completed with a few clicks.

Amazon notes three reasons developers would want to do this:

Geographic Expansion—You want to be able to launch your application in a new Region.

Migration—You want to be able to migrate your application from one Region to another.

Disaster Recovery—You want to back up your data and your log files across different geographical locations at regular intervals to minimize data loss and recovery time.

Customers will be "charged the regular data transfer prices when you copy snapshots between Regions."

Of course, EBS volumes aren't the only component developers have to handle. What about the virtual machines that host operating systems and applications? Amazon has plans for those too. "As a next step, we will implement copying of AMIs (Amazon Machine Images) between Regions," the company said. (Amazon Machine Images is what Amazon calls the virtual machines in its Elastic Compute Cloud.)

Despite being in "the cloud," Amazon Web Services has always required developers to know what they're doing. Customers still have to manage a lot of the infrastructure even though they're not monitoring physical servers and storage. But that doesn't mean everything has to be a hassle, so Amazon simplifying something as important as disaster recovery is a big step in the right direction.